Our invention relates to a fermentation process for preparing phenylacetic acid using phenylalanine as a starting material with the fermentation being carried out in aqueous media and in the presence of a gaseous oxygen-containing composition such as air using an organism of the Pseudomonas genus or of the Comamanas genus or a mutant thereof. The organisms express enzymes which enable one or both of the reactions: ##STR1## to proceed to produce phenylacetic acid having the structure: ##STR2## in high yield.
Phenylacetic acid has been shown to be produced from phenylalanine using fermentation type reactions but the various organisms used to carry out such reactions have not produced the phenylacetic acid in commercially available yields. A need exists for producing such phenylacetic acid in commercially useful yield in view of the usefulness of such phenylacetic acid for its organoleptic properties and as an intermediate to prepare other compounds. Thus, for example, the following references indicate production of low yields of phenylacetic acid using phenylalanine as a starting material:
(i) Bourgeau, et al; CAN. J. Microbiol. 1983, 29 (9) 1184-9 (shows the use of Bacteroides gingivalis); PA1 (ii) Kohmoto, et al; J. Fac. Agr., Tottori University, 1973, 8, 21-31 (uses Rhizoctonia solani); PA1 (iii) Yuasa, et al; Agric. Biol. Chem., 1976, 40 (9) 1679-85 (uses Saccharomyces rouxii); PA1 (iv) Dagley, et al; J. Gen. Microbiol, 8, 1-7 (1953) (uses Vibrio O1).
Nothing in the prior art discloses the use of members of the Comamanas or Pseudomonas genus or for that matter any other organism for carrying out the reaction: ##STR3## or the reaction: ##STR4## or the combination of reactions: ##STR5## to effect production of phenylacetic acid having the structure: ##STR6## in high yield by means of fermentation.